Access Point Name (APN) is a part of GPRS subscription data which is stored in Home Location Register (HLR) and which is transferred to the SGSN upon the activation of a GMM-Context.
APN has to be defined in HLR, Gn DN, GGSN and/or Billing or DPI’s subscriber database
APN is split into two parts :
- Network Identifier : Mandatory, eg : http://www.xlgprs.net
- Operator Identifier : Optional, except for Inter-PLMN roaming. eg : mnc011.mcc510.gprs
Max APN Length : 100 octets, with Network Identifier length is 63 octets and max operator identifier is for the rest.
We also know the wildcard APN (*). There are wildcard APN (*) on HLR. Which can allow user to not request a specific APN to do PDP Context Activation.
As a subscriber, we just know the used of APN on the GPRS setting on our handset or dongle/modem.